There's an old Microsoft game that was made open source some years ago.
It's a multiplayer hybrid of Real time strategy, First person shooter, and space simulation and is all played out in a full 3D playing field.
Most maps consist of many sectors, linked by "alephs" or wormholes.
Each sector contains various asteroids, generic, he3, Carbon, Silicon, and Uranium.
Each team starts off with a Garrison, a large tough space station capable of building miners and various constructors.
-Miners fly to He3 asteroids for gathering resources, sectors usually have 2-4
-Outposts and Teliport recievers are built on generic rocks, the most common.
-Supremacy centers are built on a carbon asteroid, they carry out research for bettering ship tech and the main unit is the Fighter, a very versatile unit.
-Expansion complex is built on the uranium asteroid and includes upgrades to minning and defensive tech. The main ship is the Interceptor, fast and tough, but short ranged and very low scanning abilty.
-Tactical lab is build on the silicon asteroid, this is tech path accels at ruining the other team's economy, but is very difficult to defend with. It involves research of cloaking and energy technology.
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